2026 Trek Speed Concept SLR vs 2025 Specialized Tarmac SL8 LTD
We can't match sizes for these two: one of them has no stack and reach for the sizes shown.
What changes on the Specialized Tarmac SL8 LTD
- Frame stack
- n/a
- One of the bikes has no number for this
- Frame reach
- n/a
- One of the bikes has no number for this
- Wheelbase
- −69 mm
- Shorter: quicker to change direction
- Head angle
- +0.5°
- Steeper: sharper steering
- Chainstays
- ±0 mm
- About the same
The two frames
We can't draw these frames yet. The Trek Speed Concept SLR numbers we have for size XL are missing the seat angle. The numbers below still compare.
Geometry side by side
| Measurement | Trek Speed Concept SLR XL | Specialized Tarmac SL8 LTD 54 | Difference |
|---|---|---|---|
| Reach | 445 | not listed | |
| Stack | 565 | not listed | |
| Head tube angle | 72.5° | 73° | +0.5° |
| Effective top tube | 565 | 541mm | −24 mm |
| Chainstay length | 410 | 410mm | ±0 mm |
| Wheelbase | 1047 | 978mm | −69 mm |
| BB drop | 80 | 72mm | −8 mm |
| Standover | 831 | 768mm | −63 mm |
| Seat tube length | 574 | 473mm | −101 mm |
| Head tube length | 140 | 137mm | −3 mm |
| Seat tube angle | not listed | 74° | |
| BB height | not listed | 268mm | |
| Fork length | not listed | 370mm |
Differences are the Specialized Tarmac SL8 LTD minus the Trek Speed Concept SLR. Full charts: 2026 Trek Speed Concept SLR, 2025 Specialized Tarmac SL8 LTD.
Where each sits in its class
Trek Speed Concept SLRSpecialized Tarmac SL8 LTD
Each bike is ranked against its own type on Quiver (triathlon and road), on frame geometry alone. Not your hand position or ride feel.
What each ships with
The stock build of each bike's first listed trim. Parts that match are dimmed.
| Part | Trek Speed Concept SLRSLR 7 | Specialized Tarmac SL8 LTDS-Works LTD |
|---|---|---|
| Frame | Trek Speed Concept | Specialized S-Works Tarmac SL8 FACT |
| Fork | Trek SC | not listed |
| Shifter | Shimano Dura-Ace R9180 | SRAM RED AXS |
| Derailleur | Shimano Ultegra R8150 Di2 | SRAM Red AXS |
| Cassette | Shimano Ultegra R8101 | SRAM RED XG-1290 |
| Chain | Shimano XT M8100 | SRAM RED |
| Crankset | Shimano Ultegra R8100 | SRAM RED AXS Power Meter |
| Wheelset | Bontrager Aeolus Pro 51 | Roval Rapide CLX II |
| Tire | Bontrager R3 | Specialized S-Works Turbo Rapidair 2Br |
| Brake | Shimano Dura-Ace R9270 | SRAM Red AXS |
| Seatpost | Trek Speed Concept SLR | not listed |
| Saddle | Bontrager Hilo | Specialized S-Works Power |
| Bottom bracket | not listed | SRAM DUB |
| Handlebar | not listed | Roval Rapide Cockpit |
| Stem | not listed | Roval Rapide Cockpit |
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